The new Kiwi Rail Locomotive wash slab in Christchurch was designed to be watertight without any joints. Dramix 5D structural steel fibre was used to provide additional capacity in the foundations and was also used in the slab to design for a nominal crack width of 0.2mm.
The new Perth BUSPORT required a water tight raft slab. BOSFA were able to support the design engineer’s BG&E to produce calculations for their nominated crack width.
The major components of this project constructed in Forrestfield, Western Australia for
Western Power consists of three large bund areas which are designed with a crack width criteria
of 0.2mm, this was achieved by using a combined reinforcing method of DRAMIX
steel fibres and traditional reinforcing.
Project Completed in 2012
Detailing the slab with joints to guarantee avoiding uncontrolled cracking under service stresses wouldn’t have been possible. The Dramix® 4D Combi Slab solution took this restraint into account and enabled the construction of a joint free floor.
Hamilton, NZ
For the same crack width design, the use of one layer of mesh (7.5mm wires at 150 c/c transversely and 100mm c/c longitudinally) plus Dramix®, resulted in a cost effective solution that was simpler and quicker to construct.
A conventionally reinforced solution would have required 2 layers of reinforcing bars to ensure a crack width of 0.2mm.
To achieve the same crack width, the Dramix® Combi Slab solution only required one layer of bars plus Dramix®. A simpler, faster and more cost effective option to construct.
Leakage of containment bunds can be an issue and costly to put right. Typical design and construction has sealed joints and expensive water stops. However, if the bund cracks outside these control points then there commonly isn’t enough reinforcing to control them to acceptable levels. Alternatively, heavy top and bottom reinforcing can be used to reduce the number of joints, this is expensive and difficult and time consuming to construct.
TYPE OF APPLICATION:
Joint free liquid tight slab
2012:
North Island, New Zealand
This project required a joint free watertight slab to support tanks containing water and fertilizer. This required a crack width calculation of 0.2mm.
SA Water engaged SMEC Engineering to design a 400m long flood channel to cope with a high water flow of 20m/sec. A channel of this size poses numerous detailing and construction issues, however the adoption of the Dramix Combi Slab solution ensured simplification of the traditional steel, removal of water stop joints, allowed for a quicker construction programme and met the required crack width requirement of 0.2mm.